NESTING HABITS OF BIRDS. 159 
Many other well-authenticated incidents of a similar 
nature are recorded. A cat-bird placed its nest on two 
bushy limbs that grew close together. The weight of the 
structure spread apart the slender branches, when the 
birds fastened them together by some fine strips of bark. 
The weaver bird has a most curiously shaped nest, a 
specimen of which is before me, sent from Calcutta to 
a member of the “Society of Natural Sciences.” It is 
a well woven elongated pouch, almost water tight, 
small at the upper end, about a foot and a half in length 
and composed of strong fibre and grass about the color 
of a cocoanut. It is a pensile nest, cunningly and 
securely fastened to a branch above it, and wholly 
closed at the top. The entrance is a sort of gallery on 
one side, opening from beneath, and a little below the 
line with the bottom of the nest. In this orifice, the 
bird ascends two or three inches and then settles into 
the nest, being entirely shut out from the world and 
securely sheltered from sun and storm. Mr. Pohlman 
saw large numbers of these nests high in trees over- 
hanging the Paraiba River, South America. 
The summer yellow bird (Dendroica estiva) surpasses 
all other birds in its exercise of sagacity in preparing 
for its offspring. It is well known that the cow bunt- 
ing often lays its eggs in the nest of this bird, for incu- 
bation, thus escaping the cares of maternity. To foil 
this, the cunning little warbler often builds a tall or 
double-headed nest, and if the bunting deposits her egg 
first, a wall is built over it, and the bird lays her own 
eggs; if the intruder’s egg is laid after her own, then 
